Zinsco Q60 Miniature Circuit Breaker

The Q60 is a plug-on miniature circuit breaker designed specifically for legacy Zinsco load centers. It provides an exact fit for these discontinued panels, eliminating the need for complex retrofitting.

Original Zinsco breakers are obsolete, but the Q60 can be cross-referenced with the Connecticut Electric UBIZ60. These aftermarket replacements are engineered to match the physical dimensions and connection points of the original Zinsco Q-series.

The breaker features standard mechanical lugs that accept either copper or aluminum conductors. For a 60-amp circuit, the terminals accommodate wire gauges from 6 AWG to 4 AWG. Always verify local code requirements for conductor sizing based on the specific load and insulation temperature rating.

Zinsco load centers have well-documented historical reliability issues, particularly concerning the aluminum busbars and breaker connection points. When installing a replacement Q60, a licensed electrician should thoroughly inspect the panel busing for pitting, corrosion, or signs of arcing before seating the new breaker.

The breaker uses a fixed thermal-magnetic mechanism with Long-Time and Instantaneous (LI) trip functions. The thermal element provides a delayed trip to prevent nuisance tripping during temporary overloads, while the magnetic element trips instantaneously to clear severe short circuits up to its 10kA fault current rating.